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G Faa

Publications and source records attributed to G Faa.

At least 55 records · Page 3Linked to original sources
PubMed1995

Endometrial polyps with predominant stromal component are characterized by a t(6;14)(p21;q24) translocation.

Cytogenetic investigation of endometrial polyps revealed the presence of a t(6;14)(p21;q24) as the sole abnormality in three cases. All tumors showed a histopathological pattern of predominant stromal hyperplasia with scarce representation of glandular elements, suggesting that a cytogenetic subgroup characterized by the t(6;14) translocation can be associated with endometrial polyps with a preponderant component of mesenchymal origin.

Adult↗
PubMed1995

Uneven hepatic copper distribution in Wilson's disease.

BACKGROUND/AIMS: Determination of hepatic copper concentration is important in the diagnosis of Wilson's disease. We studied copper distribution in the cirrhotic liver of a patient who died of Wilson's disease. METHODS: A liver slice extending from the left to the right lobe was divided into 38 samples. Each sample was analyzed for copper content by Induced Coupled Plasma Atomic Emission Spectroscopy. RESULTS: The mean copper concentration in the liver was 1370 micrograms/g dt. A striking variability, up to 2-3-fold, in copper levels was observed between the samples: the copper concentration ranged from 880 to 2100 micrograms/g dt, with significant differences even between adjacent samples. Lobar differences were also observed, with a tendency of the right lobe to accumulate more copper than the left lobe. Histochemical analyses confirmed the uneven distribution of copper even at the acinar level. Copper was mainly stored in periportal hepatocytes (zone 1) and at the periphery of the regenerating nodules. Moreover, we observed some nodules with the majority of hepatocytes full of copper granules, adjacent to areas of parenchyma negative for copper stains. CONCLUSIONS: Our data show that: 1) copper is unevenly distributed in Wilson's disease in the cirrhotic stage; 2) a lobar pattern of copper distribution is evident in this case, characterized by a higher copper concentration in the right lobe; 3) the observed lobar pattern is different from that described in the newborn liver, characterized by a higher copper content in the left compartment of the liver; 4) copper content determined in a small liver sample cannot be considered as absolutely representative of the mean hepatic copper concentration. From a practical point of view, our data show that sampling variability deserves more consideration in the diagnosis and in the monitoring of Wilson's disease. The use of hepatic copper concentration in monitoring the efficacy of the copper-chelating therapy may be unreliable, particularly in the cirrhotic stage, because of the patchy distribution of copper, as demonstrated in this study.

Adult↗
PubMed1995

Chemometric methods applied to an ICP-AES study of chemical element distributions in autopsy livers from subjects affected by Wilson and beta-thalassemia.

The concentrations of seven elements (Ca, Cu, Fe, Mg, P, S and Zn) in three autopsy livers (from two beta-thalassemic patients and one Wilson's disease patient) were determined by ICP-AES technique. At autopsy the three livers were subdivided into a large number of samples for a detailed study of the distribution of Fe and Cu, the accumulation of which characterizes the two diseases. In the same samples Ca, Mg, P, S and Zn concentrations were also determined in order to study significant variations or anomalous trends that could help identify these diseases. Our results generally show a good coincidence with literature data within the limits of sample variability. Based on Factor Analysis as well as Regression Analysis there is evidence of a high correlation between Fe and P contents in beta-thalassemia. The latter finding led us to propose tentatively an accumulation of Fe as a complex with P-containing molecules.

Adult↗
PubMed1994

Numerical chromosome changes in a nasal polyp.

The etiology of nasal polyposis is not fully understood. We found numerical chromosome changes in one out of five cytogenetically investigated nasal polyps. The histological picture of this case was characterized by the presence of histiocyte-like cells, which were absent in the remaining cytogenetically normal polyps.

Adult↗
PubMed1994

Familial cardiomyopathy, mental retardation and myopathy associated with desmin-type intermediate filaments.

The clinical and morphological findings of a familial case affected by mental retardation, severe biventricular hypertrophic cardiomyopathy and vacuolar myopathy are reported. The phenotype of this patient is similar to that described by other authors, in which a lysosomal glycogen storage disease with normal acid maltase levels was suspected. However, in our case the vacuoles were stained by several antibodies directed against various sarcolemmal proteins, such as dystrophin and spectrin, and therefore, were not of lysosomal origin. Some of these vacuoles were clearly derived from the splitting of the fibres and invagination of the extracellular space; autophagic vacuoles were not observed. The accumulation of desmin-type, intermediate filaments was demonstrated on immunocytochemistry both in the skeletal and cardiac muscles. A brother of the propositus was also affected by mental retardation, severe cardiomyopathy and died suddenly at the age of 24 yr. A cardiomyopathy and mental subnormality were also present in other male cousins of the proband, while sudden death occurred in several females relatives, whose intelligence was normal. None of these latter individuals was available for further investigation. This report expands the spectrum of desmin associated myopathy and cardiomyopathy to include a familial condition with associated mental retardation.

Adult↗
PubMed1994

Effect of iron overload on the response to recombinant interferon-alfa treatment in transfusion-dependent patients with thalassemia major and chronic hepatitis C.

The purpose of this study was to determine whether interferon-alfa (IFN-alpha) therapy benefits patients with transfusion-dependent thalassemia and chronic active hepatitis C, and whether their iron burden modifies the response to this therapy. We conducted a controlled trial of recombinant IFN-alpha (3 million units per square meter of body surface area, three times a week for 15 months) in 65 patients with thalassaemia major and chronic active hepatitis C; 14 of them were untreated control subjects. In 21 of the 51 treated patients, alanine aminotransferase values returned to normal within 6 months, and hepatitis C virus ribonucleic acid was no longer detected in serum; no changes were detected among control subjects. The response to IFN-alpha therapy was inversely related (p < 0.002) to the liver iron burden as assessed by atomic absorption, the histologic semiquantitative method, or both methods. During 3 years of follow-up, two responder patients had relapses. We conclude that IFN-alpha represents a useful therapeutic option for children with transfusion-dependent thalassemia and chronic active hepatitis C with a mild to moderate iron burden.

Adolescent↗
PubMed1994

Iron concentration and distribution in the newborn liver.

Recent observations on a correlation between fetal serum ferritin and gestational age, consistent with an increase in fetal iron stores during pregnancy, led us to study liver iron content in 22 human stillborns, newborns and infants of different gestational and postnatal age. At autopsy, a longitudinal liver slice was subdivided into ten blocks. Each sample was analyzed for iron content by atomic absorption spectroscopy. The mean iron concentration in the studied livers was 21.6 microM/g dry tissue (d.t.). A striking interindividual variability in iron content was observed: the hepatic concentration of the metal ranged from 3.3 to 64.4 microM/g d.t. No correlation was found between the hepatic iron concentration and gestational age or other clinical parameters of the patients studied. Moreover, the total storage iron of the liver did not appear to be correlated with the gestational age. The analysis of iron concentration in ten blocks in each liver revealed an irregular distribution of the metal. Lobar differences were observed, with a tendency of the left lobe to accumulate more iron than the right one. Furthermore, striking differences in iron content were found between adjacent liver samples, ranging in one instance from 4.5 up to 109.0 microM/g of dry tissue. Perls' stain for iron was positive in 7 out of the 22 livers examined, showing an irregular acinar distribution, with preferential periportal localization. Our data show that the newborn liver can be considered an interesting model for the study of iron storage.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1994

An electron microscopic study of apoptosis induced by cycloheximide in rat liver.

A histological and ultrastructural study, coupled with transmission and scanning electron microscopy of the early changes in the liver following a single administration of cycloheximide (CHX), was carried out in male Wistar rats. At the histological level, apoptosis was already present in the liver 2 h after treatment. By scanning electron microscopy, the following sequential changes were observed: brightness and progressive detachment of hepatocytes from neighbouring cells, formation of surface infolds with multiple blebs and, finally, release of several membrane-bounded apoptotic bodies (ABs) in the extracellular space and into the sinusoidal lumen. Three hours after CHX administration, the apoptotic cycle was completed, as shown by the presence of phagocytosed ABs inside the cytoplasm of intact liver cells. Light microscopic examination of the liver 6 h after CHX administration showed ABs mainly located in the cytoplasm of intact hepatocytes and inside activated Kupffer cells. By transmission electron microscopy, it was possible to demonstrate that cells undergoing apoptosis were hepatocytes. At 24 h, the livers of treated animals appeared normal, with no evidence of apoptosis.

Animals↗
PubMed1994

Scanning electron microscopy of chronic hepatitis C. An OsO4 maceration study on human biopsies.

A study at the scanning electron microscope (SEM) on the liver changes in chronic hepatitis C was carried out in human needle biopsies from four patients. Intracellular structures were visualized by a novel modification of the OsO4 maceration method that allows to investigate human pathological specimens. At low magnification we observed both sinusoidal and hepatic cells alterations: sinusoids appeared occluded by lymphocytes, hypertrophic Kupffer cells, activated perisinusoidal cells, necrotic material and apoptotic bodies. Some hepatocytes showed ballooning, arrangement in rosettes, and structural changes related to apoptosis: cell rounding, detachment from neighbouring cells, clustering of cytoplasmic organelles and cell fragmentation. We also found periterminal, sinusoidal, and pericellular severe fibrosis, and bile duct damage of moderate degree. At higher magnification, after removing the intracellular matrix, all the intracellular structures appeared normal, except for focal dilatation of smooth endoplasmic reticulum. Our findings clearly demonstrate the usefulness of the OsO4 maceration method for the study of chronic hepatitis and of liver disease in general. Thank to this technique, in fact, SEM becomes a diagnostic tool complementary to light microscopy and transmission electron microscopy (TEM), for its unique ability to give both low magnification panoramic views and detailed high magnification 3D images of cell organelles.

Biopsy, Needle↗
PubMed1994

Immunohistochemical and genetic characterization of the M Cagliari alpha-1-antitrypsin molecule (M-like alpha-1-antitrypsin deficiency).

BACKGROUND: Genetic alpha-1-antitrypsin (AAT) deficiency may be due to defective secretion, intracellular degradation, or lack of synthesis. Defective secretion results in hepatocytic storage and liver disease. These two events occur only with the common deficiency variant, Z AAT, and with a few rare deficiency variants, called M-like. Hepatocytic storage of AAT (either Z or M-like) can be demonstrated in tissue sections by specific immunostaining with a polyclonal anti-AAT antibody, that recognizes all variants of AAT. A monoclonal antibody capable of selectively and exclusively reacting with Z AAT has been generated and successfully used in both serum and tissue studies. EXPERIMENTAL DESIGN: To determine whether a new M-like variant, M Cagliari, carries a mutation different from Z AAT, we have compared antigenic properties and DNA sequences of the two variants. Liver tissue sections from PiZ and PiM Cagliari patients were stained with both polyclonal anti-AAT and monoclonal anti-Z AAT antibodies. DNAs were polymerase chain reaction-amplified with AAT-specific primers and sequenced. RESULTS: Liver tissue sections from PiZ livers were positively stained with either the polyclonal or the monoclonal antibody. The PiM Cagliari liver sections reacted with the polyclonal antibody, but not with the monoclonal anti-Z AAT, thus indicating a difference in antigenicity from Z AAT. Accordingly, DNA analysis ruled out a Z mutation and revealed a microdeletion in exon II, identical with M Malton. CONCLUSIONS: A simple immunohistochemical assay based upon the application of both polyclonal and monoclonal antibodies represents a reliable test to distinguish Z and nonZ AAT deficiencies, thus assisting in the selection of cases worthy of more time-consuming analyses such as DNA sequencing. The same approach may be used for the characterization of as yet undefined PiM cases with AAT liver storage.

Adult↗
PubMed1992

Mitogen-induced liver hyperplasia does not substitute for compensatory regeneration during promotion of chemical hepatocarcinogenesis.

Experiments were designed to determine the efficacy of different types of liver cell proliferative stimuli given during exposure to several liver tumor-promoting regimens, on the formation of foci of enzyme-altered hepatocytes. Male Wistar rats were initiated with diethylnitrosamine (150 mg/kg body wt). After a 2 week recovery period animals were subjected to promoting regimens, the resistant hepatocyte model, the phenobarbital model and the orotic acid model. While the rats were on these regimens they were given liver cell proliferative stimulus, either a compensatory type (two-thirds partial hepatectomy or a necrogenic dose of carbon tetrachloride) or a direct hyperplastic stimulus such as that induced by the primary mitogen, lead nitrate. Initiated cells so promoted by these regimens were monitored as foci of enzyme-altered hepatocytes positive for gamma-glutamyltransferase and placental glutathione S-transferase or deficient for adenosine triphosphatase. While carbon tetrachloride and partial hepatectomy-induced compensatory regeneration stimulated the promoting ability of the regimens used, direct hyperplasia could not stimulate the formation of foci and/or nodules from initiated hepatocytes. Evaluation of thymidine incorporation indicated that there was no significant difference in the extent of DNA synthesis in both the proliferative stimuli irrespective of the promoting procedure used.

2-Acetylaminofluorene↗
PubMed1992

Genetic variants of alpha-1-antitrypsin (AAT).

This paper reviews the genetic variants of alpha-1-antitrypsin (AAT) which have been sequenced with special emphasis on the s.c. deficiency variants. These result in AAT low plasma levels via three main mechanisms: 1) intracellular storage; 2) intracellular degradation; 3) lack of synthesis. Intracellular storage occurs with the classical Z variant and with a few variants called M-like, because of their isoelectric focusing (IF) pattern. The storage phenomenon causes liver damage and can be demonstrated at both light and electron microscopic level with the help of immunohistochemistry. We report a new deficiency variant of AAT (M-Cagliari) characterized by very low plasma levels, massive storage of AAT and liver cirrhosis. By using immunohistochemical techniques and DNA analysis we could demonstrate that M-Cagliari has antigenic and genetic properties other than the Z AAT.

Base Sequence↗
PubMed1992

The myoepithelial and basal cells of ducts of human major salivary glands: a SEM study.

The cytoarchitecture and distribution of myoepithelial (mecs) and basal (bc) cells of intralobular (intercalated, striated) and interlobular (excretory) ducts of human major salivary glands were studied by SEM through a variety of maceration and microdissection techniques. Intercalated ducts are covered by mecs which, unlike the large stellate cells of acini, are spindle shaped. Small star shaped mecs are rarely observed even in the most distal striated ducts, while no such cells are seen in excretory ducts. Basal cells form a more or less continuous row of small, basally placed cells in excretory ducts. Sparse bc are occasionally present in proximal striated ducts as well. Following microdissection, bc exhibit a cup-shaped apex which embraces the convex base of principal cells. This configuration may explain why, in TEM, bc seem to possess lateral processes which may be mistaken for mecs processes. Moreover, the lateral surfaces of bc do not exhibit the complex system of plasmalemma folds typical of principal cells. The present study demonstrates that fusate mecs are present in intercalated ducts and that basal cells are distinct from myoepithelial cells. These results may have some relevance in histogenetic studies of salivary gland neoplasms.

Adolescent↗
PubMed1992

Early ultrastructural changes during thioacetamide-induced apoptosis in rat liver.

An histological and ultrastructural study of the early changes in the liver following a single administration of thioacetamide (TH), was carried out in male Wistar rats. One hour after treatment, apoptosis was already present in the liver. By electron microscopy, the following sequential changes were observed: progressive detachment of hepatocytes from neighboring cells, formation of surface infolds with multiple blebs and, finally, release of several membrane-bounded apoptotic bodies in the extracellular space and into the sinusoidal lumen. Three hours after TH administration, the apoptotic cycle was almost entirely completed, as shown by the presence of phagocytosed apoptotic bodies inside the cytoplasm of intact liver cells. Our study evidences that TH induces apoptosis of liver cell as early as one hour after its administration. Moreover, our data show that the apoptotic cycle may be completed in 3-4 h. From the morphological point of view, apoptosis induced by TH appears indistinguishable from programmed cell death, occurring during embryogenesis or metamorphosis, and from apoptotic cell death seen during regression of mitogen-induced rat liver hyperplasia.

Animals↗
PubMed1992

Rapid induction of apoptosis in rat liver by cycloheximide.

A single administration of the inhibitor of protein synthesis cycloheximide results in the occurrence of apoptosis in rat liver. The presence of intracellular apoptotic bodies was detected as early as 2 hours after treatment. No evidence of cell necrosis could be observed by histologic and biochemical analysis. Apoptosis was followed by an increased expression of testosterone-repressed prostate message-2 RNA, a gene whose activity has been associated to apoptotic cell death in involuting rat prostate. The finding of in vivo induction of apoptosis in nonproliferating cells by an inhibitor of protein synthesis, together with the rapidity and synchrony in the occurrence of cell death make this model potentially useful for the analysis of the kinetics of the apoptotic cycle and in exploring some of the mechanisms of regulation of genes possibly involved in this type of cell death.

Animals↗
PubMed1991

Uterine leiomyoma cytogenetics. II. Report of forty cases.

Chromosome analysis of 40 cultured uterine leiomyomas revealed the presence of clonal changes in 32.5% of them, confirming the cytogenetic heterogeneity within this type of tumor, mostly referable to a few cytogenetic subgroups. Preferential involvement of 12q14-15 and 14q23-24 bands in reciprocal and complex translocations was most commonly observed. Deletions of chromosome 7 and changes of chromosomes 1, 2, and to a lesser extent, chromosomes 19 and 22 were also found. Constitutional karyotype of patients bearing tumors with karyotypic abnormalities was examined. In one patient, two cells were found with t(12;14)(q14-15;q23-24) translocation and two with del(14)(q13q23-24). The latter rearrangement was also present as a clonal change in the tumor.

Chromosome Deletion↗
PubMed1991

Identification of PiZ gene products in liver tissue by a monoclonal antibody specific for the Z mutant of alpha 1-antitrypsin.

Globular inclusions of abnormal alpha 1-antitrypsin (AAT) in the rough endoplasmic reticulum of hepatocytes is a characteristic feature of AAT deficiency of the PiZ phenotype. It is also seen in some rare M-like Pi types (including M-Cagliari) having low plasma AAT levels and M-like mobility on isoelectric focusing. In this report the ability of a monoclonal antibody (ATZ 11) raised against PiZ hepatocytic AAT to identify AAT inclusions by immunohistochemical techniques is evaluated. The antibody was found to specifically and selectively identify the PiZ gene products in hepatocytes, but not M-Cagliari AAT. Application of the method thus allows distinction of PiZ gene carriers from PiM-like subjects in the absence of serum protein analysis.

Antibodies, Monoclonal↗